Automatic pusher assembly



Nov. 5, 1957 P. AMERIO ETAL 2,812,050

AUTOMATIC PUSHER ASSEMBLY Filed July 24, 1956 3 Sheets-Sheet 1 INVEN TOR. PASQUALE AMERIO ueusr KRAFT gm; F

T HE! R ATTORN EY.

Nov. 5, 1957 P. AMERI O ETAL 2,812,050

AUTOMATIC PUSHER ASSEMBLY Filed July 24, 1956 3 Sheets-Sheet 2 FIG. 2

VIIIIIIIIIIIIIIII IIIIIIIIIIIIII'IIII FFL REV. FOR.

. INVEN TOR. PASQUALE AMERIO AUGUST KRAFT ym i WM H R ATTORNEY.

Nov. 5, 1957 4 P. AMERIO ETAL 2,812,050

AUTOMATIC PUSHER ASSEMBLY Filed July 24, 1956 3 Sheets-Sheet 3 OFF I2 UTO INVENTORS'. PASQUALE AMERIO UGUST KRAFT THEIR ATTORNEY.

MAN.

A.C. SUPPLY United States Patent AUTOMATIC PUSHER ASSEMBLY Pasquale Amerio, Erskine Lakes, and August L. Kraft, Roselle Park, N. J., assignors to Amerio Refrigerating Equipment Co., Inc., Union City, N. J., a corporation of New Jersey Application July 24, 1956, Serial No. 599,749

10 Claims. (Cl. 19831) This invention relates to the freezing of foods and relates more particularly to an improved freezer unit having automatic or semi-automatic means for feeding boxes of the unfrozen foods to the freezer unit which is formed with a charging opening in a front wall and a discharge opening on substantially the same plane in a rear wall.

An important object of the present invention is to provide a novel pusher assembly for moving columns or groups of boxes from a conveyor into the freezer.

The freezer unit preferably has a plurality of superimposed freezer plates which are supported in a vertically movable cradle so asto successively position two adjacent plates at the charging opening. Means are also provided for increasing the normal spacing between these two adjacent plates in order that the boxes may move into the cavity without obstruction.

The particular means for raising and lowering the plates and for securing this increased spacing is the subject of my application Serial No. 600,527, filed July '27, 1956.

Another object of the present invention is to'prov'ide an improved freezer loading apparatus which eliminates the need for placing the boxes of the unfrozen foods into trays for introduction to the freezer. The boxes are fed by an automatic conveyor system which arranges them in groups with a pre-determined' spacing between each group and the pusher assembly of the present invention wipes the group off the conveyor and into the freezer and I this operation continues until enough groups or rows have been delivered to completely fill the cavity, after which the cradle is moved to position a new cavity at the charging opening.

Another object of the invention is to provide a completely automatic pusher assembly for plate freezers wherein the pusher operates until a plate is filled and then recommences operation when another plate is aligned with the charging opening.

A further object of the invention is to provide means for raising the pusher bar on its return stroke so that it does not encounter a new group of boxes which has now been delivered to the loading zone of the freezer.

Yet another object of the invention is to provide novel means for breaking the bond which has formed during freezing between the boxes and the plates. A separate breakaway stroke is provided when the charge of boxes is to be removed from the plates and this avoids crushing of the unfrozen boxes with their soft contents which would occur if the latter were employed to break' the bond.

In the drawings: i '7 Fig. 1 is, a front elevation of a freezer embodying the present invention. V

Fig. 2 is a side elevation thereof, partially in section.

Fig. 3 is a side elevation of the pusher assembly and showing the position of the pusher when it has about half if completed its forward or loading stroke. t

Fig. 4 is a similar view but showing the pusher as it "ice i Fig. 5 shows the pusher in elevated position during the i return stroke.

Fig. 6 shows diagrammatically the several positions of the pusher guide pin during its travel around the cam block during a complete cycle of operation.

9 Fig. 7 is a schematic diagram of the cylinder and piston which controls the pusher. The valve which operates it by electromagnetic control means is also shown.

. Fig. 8 shows a circuit for. controlling operation of the pusher assembly.

v Fig. 9 is a broken section of the freezer and showing the mechanical details of the catch arms which support the platens during loading.

The freezer of the present invention includes a generally rectangular insulated housing having a front wall 10, a rear wall 11, a top wall 12 and side walls 13. The

' front wall may have two upper panels 14 and one lower --vertically movable hydraulic ram'shown schematically at 21 and the whole bank of plates are intermittently moved up and downto successively position two adjacent plates in horizontal alignment with elongated openings 22 and 23 in the front and rear walls, respectively. Each opening is shown as being defined by upper and lower angle bars 24 and 25.

' The two plates 19 and 20 shown as being in alignment V with these openings having a spacing therebetween which isgreater than'the height of the boxes of comestibles in order that they may be readily moved into and out of the freezing area without obstruction.

A group of boxes of food are fed to a position in alignment with the elongated charging opening 22 by means of a conveyor which may comprise an endless belt 26. The length of each plate is suflicient to support ten to twenty boxes in side by side relation and the width ofthe plate is sufficient to receive a given number of rows, dependent upon the size of the boxes. When one cavity is filled a new one is presented and this continues until the freezer is filled and the freezing continues during the loading operation. The actual time for filling the freezer may take only 10 to 15 minutes and after filling the goods are allowed to completetheir freezing .period after which the boxes are removed as the unfrozen boxes are again moved into the freezer. The unfrozen boxes are soft and the frozen boxes have congealed to the plates. Accordingly the first step on the new cycle is to move the pusher against the last group to break this :bond. The discharging and refilling then starts and the cycle repeated. The frozen boxes are discharged through rear wall opening '23 onto a second moving conveyor 30.

J The pusher assembly includes a bell crank arrangement :comprising a shaft 31 journalled at its ends in bearings 32 carried on vertical frames 33. Rocking motion is imparted to the shaft by means of an upper lever 34 keyed ythereto which is moved back and forth by a piston in cylinder 35 connected by a link 36 to lever 34.

The bell crank lever further includes two lower rocker arms 40 keyed to the shaft at 41 and at the lower end a clevis 42 is formed which receives a pivot pin 43 forming a support for a rearward'extension 44 of a'pusher bar 45 of angular construction.

commences its return stroke afterthe' loading operation. 7 i

. When the pusher bar moves forwardly it is in itsloweropening during this returnstroke.

into storage tank 81.

most position of Fig. 3 andduring its return stroke it is ment of thebar is controlled by-anauxilia'ry lever 46 pivoted at its lower end at 47 on the pusher bar and having a pin 50 at its upper end which is positioned'in a vertical slot 51 in rocker arm '40. Movement of each lever is controlled by means of a pin 52 carried thereby which is guided around a cam block 53 pivoted at 54 on a flat cam support 55 having a'fiange 56 around its top, bottom and rear edges. Cam block 53 is generally 'rectan gular except for a downwardly inclined front edge 60.

During forward travel of the pusher, pin 52 underlies the cam block and such pin is supported on lower flange 56. When this pin clears the forward .point of the block the front end of the latter falls to the position of Fig. 4'due to gravity and at this moment the pusher commences its rearward travel with the pin climbing the diagonal edge. Cam supports 55 are secured to frames 33. A spring 61 provides a positive drive downwardly for lever 46. The pusher is shown in an advanced position in Fig. in broken lines This additional stroke is employed to break all the boxes loose from the freezer plate after freezing has been completed.

The cycle of operation isillustrated diagrammatically in Fig. 6. Pin 52, which controls travel of the pusher bar and whichtravels around and forwardly of cam block 53, is shown in four positions, to wit: IL (intermediate limit or starting position); RL (rear limit or I position for starting forward box feeding stroke); FL

(forward limit during box feeding stroke); and FFL (full forward limit at the end of the break-away stroke).

Details .of the cylinder 35 are shown in Fig. 7. The cylinder includes two heads 65 and 66, and apiston 67 which is secured to a shaft 68 extending through both jheads.

75 is pulled to the right; therebynaligning two straight vents 82 with conduits 70, 80 and -71, 78. and allowing liquid to flow from conduit 78 through conduit .71 to head 66 andmovethe' piston 67 to the left. As the piston moves to. the left, liquid will be forced through h'ead 65, conduit 70, the left vent 82, through conduit '80, and When current is 'rem'ovedfrom solenoid 77, the shaft 75 and the valve-piston 174 are returned to the off" position by a spring (not shown) and the movement stops.

, Pistonl67 is moved to the right (and the pusher to the left as seen in Fig. 2) by theactuation of solenoid coil 76 and a movement of shaft 75 to the left.

This action aligns crossed vents 83 and the liquid under pressure is admitted to head 65.

Control for the pusher 45"and1thewoperationrof cylinder 35 is effected by a counting and co'ntrolcircuit shown in schematic form in Fig. 8. The counting'control includes a counting relay assembly which comprises a count control. winding 86, an armature 87, a reset winding 88, a rack bar 90 driven by a pawl 91 on thearmature, a pair of normally open contacts 92 closed each time the armature is actuated, and afplurality of contacts 89 associated with a pre-set dial contact'means 99 which will be described later.

Up and down move-.

y are operated by a contact knob 97 on shaft 68.

contacts 92 are closed. This relay operates the forward ('For.) solenoid 77 and thereby operates the pusher. A reverse relay 142 is operated by a forward limit switch (FL) and controls the reverse (Rev.) solenoid 76, thereby moving the pusher backto its normal position. An Up relay 151 is operated by the set Count contact in the pre-set dial array. The Up relay is operated each time a platen is filled with unfrozen boxes and its operation causes the actuation of a solenoid (Up) winding "a newcount. A catch (8) relay 99 is also actuated by the catch-limit switches, acting through contacts on the and catc'h('A) relays. When this relay is actuated lthe 'Up solenoid is dc-energized and the platen to be filled islowered'slightlyagainst stops. The platen is now ready to receive unfrozen boxes.

A platen 'relay99 is actuated by platen loading limit (PLL) switches'acting through contacts on relay 5. The platen'relay causes the pusher arm to go to its full for- Wardlimit to break loose the frozen boxes. An 'overcount relay 109 is actuated only when an overcount has been made by the. count circuit 85. When the overcount relay is actuated, all operations stop and an attendant must inspect the control system and reset the count dial before operations can continue.

The control circuit also includes a solenoid 95 which i is operated whenall'the platens have been filled and the platen assembly'is in its lowest position, 'in the act of being'fr'ozen. Solenoid 95 (Down) is energized through a lower limit' switch 96 (LL-1) and exerts alight pressure onthe'pl'aten assembly to cause complete contact of platen surfaces and boxes.

The control circ'uit also includes four switches which The switches are actuated when the pusher'bar 45 is in predetermined positions. When the bar is in its full forward limit (FFL) 'in'the act'of breaking loose frozen boxes, switch 98 is actuated. When the bar is in the usual forward limit (FL) after having pushed a row of boxes onto a platen, switch 100 is actuated. When the. bar is in its intermediate position (or starting position) (IL) switch 101 is actuated as shown in Fig. 7. When the bar is in its rear limit position '(RL) switches 102 and 103 are actuated.

When the platen assembly is raised and each platen area is filled, the top platen surface is raised toward the 'top wall and when the last platen area has been filled, an additional upward motion closes an upper limit switch (UPL) 104 by Contact with a rod 105 which is secured to the ltop platen and extends through a hole in the (shownin dotted lines) as they are moved into position i The control circuit also includes seven relays; The function of these relays may be generally described as by the belt 26. During the loading operation motor 106 is running, because its supply circuit is connected through 'switch 1'02, andbelt 26 is arranged to move the boxes under wheel 108 at a rate whichturns the soft wheel the inotorsine'the overrunning clutch permits the wheel to move faster than the motor shaft. As soon as the two groups are filled with boxes wheel 108 is restrained 111-its movement, a strain is put on the motor, and the motor housing 106 is rocked, thereby closing a switch 111 and sending current throughwinding 86 of the count relay 127 causing its armature to be actuated to move rack bar 90 one contact space. This circuit may be traced from terminal 112, over conductors 113 and 114, through switches 96 and 115, over conductor 116, to switch 111, then'through closed contacts 117 on the overcount relay 109, over conductor 118, through contacts 120 of the relay, contacts 121 of the count relay, over conductor 122, to the count control winding 86, and, then over conductors 123 and 124, to terminal 125.

. When the armature 87' of the count relay is actuated, an insulated portion of the armature 126 closes contacts 92and causes current to flow through winding 127 of the count relay. This circuit may be traced as before, through contacts 120 of the reverse relay, over conductor 128, through contacts 92, winding 127, and conductor 124. As'soon as the count relay is actuated, contacts 121 are broken and the current is cut off from winding 86. However, holding contacts 130 are closed and the count relay is held in its actuated condition by a circuit which can be traced from conduct-or 124, through winding 127, contacts 130, conductor 131, through the forward limit switch 100, to conductor 113. During this part of the loading operation shaft 68 is positioned so that knob 97 i actuating switches 102 and 103.

A complete cycle of one platen loading operation may be described as follows: With the pusher bar 45 in its rear position and shaft 68 causing the actuation of switches 102 and 103, main switch 132 is moved to Auto. and the sequence of operations as described above takes place. Prior to moving the switch 132 to start the automatic operation, dial switch 99 is set at a contact point which represents the number of rows of boxes which can be placed on the platen and the rack bar 90 is in its starting position wheremovable contact 133 makes electrical contact with stationary contact 134.

,When the count relay is actuated, contacts 135 are ,closed and a circuit is completed through the forward solenoid 77. This circuit may be traced from conductor 113 through contacts 135, over conductor 136, through closed contacts 137 of the overcount relay, over conductor 138, to winding 77, and conductor 124. Thi circuit causes the movement of plunger 75 (see Fig. 7) and presents vents 82 to the hydraulic system so that piston 67 is moved to the left, moving linkage 36 and bar 34 .(see Fig. 2) so that the pusher 45 is moved against the boxes and pushes them onto the platen, this position of the pusher being indicated by dotted lines in Fig. 4. When the knob 97 is moved away from switches 102 and 103, the circuit to the motor 106 is broken and the motor stops. and contacts ll are opened. However, boxes still move-along the belt and form a second row, ready for the next operation of the pusher.

As the pusher moves the boxe into the platen, knob 97 moves to the left as viewed in Fig. 2 and closes the intermediate limit switch 101. This switch operation causes no action at this time because one terminal of the switch is connected to normally closed contacts 140 (on the count relay) which are now open. The pusher continues its" motion until knob 97 makes contact with the forward limit switch 100, breaking the holding circuit ot the'count relay (over conductor 131) and normalizing all of itscontacts. Contacts 135 are opened and this break cu-ts off the current from the forward solenoid Winding 77 andthe,motion of piston 67 and pusher 45 stops. At this time, with the count control relay again in operating condition, no count action occurs because the sensing rnotor 106 cannot turn '(switch 102 being normalized) and the sensing contact 111 cannot close even though fj a full row of packages are on the conveyor belt.

When the forward limit switch 100 is actuated, the

, count relay is normalized and the reverse relay is actuated I since a circuit is completed from conductor 113,'through switch 100, over conductor 141, to the reverse relay winding 142, and to line conductor 124. As soon as the reverse relay is actuated, a holding circuit is formed which retains the armature in its actuated condition. This holding circuit may be traced from conductor 124, through winding 142, through holding contacts 143, over conduc: tor 144, through switch 102, and to conductor 113. The count relay is now normalized because the holding circuit through switch is broken. The actuation of the reverse relay opens contacts and closes contacts 145 which completes a circuit from conductor 113, through contacts 145 of the reverse relay and contacts 146 of the, Up relay, to winding 76 of the reverse solenoid, and conductor 124. This actuate plunger 79 and valve piston 74- (see Fig. 7) is moved to the left, aligning the crossed vents 83 with the hydraulic system and moving piston 67 and shaft 68 to the right as seen in Figs. 2 and 7. This action moves the pusher to the left as viewed in Fig. 2 and the pin 52 climbs the diagonal edge of cam block 53, moving the pusher over the row of boxes on the belt.

In moving from the forward limit switch 100 to the rear limit switch 102, the knob 97 passes and actuates the intermediate limit switch 101 but no circuit iscompleted since one terminal of the switch is connected (by conductor 147) to contacts on the count relay and moving contact 133 on rack bar 90. Contact 133 has been moved one space to the second contact position and therefore this line is open.

When the shaft 68 is moved so that knob 97 actuates switches 102 and 103 the reverse relay is normalized since switch 102 was in series with its holding circuit. At this time the sensing motor is started again because switch 102 sends current over conductor 148, through the motor to conductor 124. The row of boxes on belt 26 is generally completed during the return stroke of the pusher mechanism, hence the wheel 108 will cause the motor 106 to close switch 111 and another counting sequence is started. The cycles of operations are the same as before except that the movable contact 133 in the counting circuit is moved another point to the left.

The above described procedure is repeated many times, each cycle moving one row of packages or boxes from the conveyor belt onto the platen. The number of rows of boxes must be predetermined and set in the dial contact switch arm 99. Then when the required number of cycles has been operated and the plate is full, contact 133 will rest on a stationary contact which is connected to the dial arm as indicated in Fig. 8. Then as the pusher is withdrawn from the platen stroke and the shaft 68 moved to the right, knob 97 operates intermediate switch 101 and this time a circuit is completed which may be traced from conductor 113 to dial switch arm 99, to contact 133, closed contacts 140 on the count relay, over conductor 147, through switch 101, through switch 98, through the second lower limit switch 150, to the winding of the Up relay 151,- and conductor 124. This circuit operates the Up relay, opening contacts 146 and breaking the circuit through the reverse solenoid, stopping the reverse movement of the pusher at the intermediate position. v

The actuation of the Up relay also closes contacts 152, completing a circuit from conductor 113, through contacts 152, over conductor 153, contacts 154 on the catch-B relay, over conductor 155, through manual switch contacts 156, to the winding 93 of the Up solenoid. This solenoid (in conjunction with the Down solenoid) controls a vertical hydraulic piston and cylinder mechanism similar in every respect to the mechanism shown in Fig. 7 except thevertical piston is secured to a shaft which moves the platen array up and down. The Up and Down solenoids 93 and 95 control a valve similar to valve 72 shown in Fig. 7. I

When the Up solenoid is actuated, the vertical piston moves-allthe platens up until two catch arms 157'. and 158 move toward the center of the machine with their upper contact surfaces underthe edges of the platen1 9'.' Mechanical details of one of the-catches 157 is shown in Fig; 9, the-catch being urged toward' the platensby a helical"-spring"160w The catch-'armsare mounted on a hinge 161 which issecured to the base of the machine. The-platens -19--together with the boxes 110'which areto be frozen areenclosed in a frameworkwhich includesa top rod162 and'vertical' rods 163.- The hydraulic piston, similar-to piston 67; whichmoves' the platens upand down is secured to the fr'ameworb 162; 163; and the en tire array moves -upand down together. When the two catch arms 157 and 158-(SeeFig.- 8) move under' the platen surface theyactuatetwoswitches 164 and 165 moving :them-to the positions shown'in-Fig. 8. Whenboth switches, have been actuated andthe circuit which includes theUp solenoid-93 is broken andthe hydraulic piston whichmoved'the platen array in an upward-direction is-disconnected and theplatens together withtheir framework 162, 163, slowly settle until the platens held up by the catches are separated'by a small distance from the boxes immediately below the upper catch surface. When this happens the top surface of the upperplaten makes .contact with the platen limit loading switch'115, closing a circuit through the switch and actuating the platen relay 129; This circuit can be traced from conductor 113 through switch 96, platen loading switch 115,'conductor 166 through the closed contacts 167 on the catch B relay 119,'then through the winding of the platen relay 129; to conductor 124. This circuit causes theactuation of the platen relay and closes contacts 170 and 171.

When the platen relay is actuated a circuit is completed through contacts 171 which may be traced as follows: From line 113, through" closed contacts 171 of the platen relay, over conductor 172, through contacts 137 of. the overcount relay 109, over conductor 138, to the For. solenoid .77,-and line conductor 124. This circuit actuates valve 74 (Fig. 7)"and operates piston 67 to propel the pushenfrom. the intermediate position to the array of frozen food. packages on the newly exposed platen. to breakthemloose from the platen surfaces and prepare the platen for the next row of unfrozen boxes.

When the pusher is in all the way after having broken loosethe frozen packages the knob 97 on shaft 68 makes contact with the full forward limit switch 98 operating it and breaking one circuit tothe Up relay and. closing another circuit to the reset coil 88. This action actuates thereset mechanism and releases rack bar 90 so that, it is returned to-its normal or zero countposition by means of a spring. Whenswitch 98 opens the circuit to conductor 173 to switch 150 and normalizes the Up relay the reverse solenoid is actuated because of a circuit which may be traced from conductor 124 through the solenoid winding 76, through closed. contacts 146, through closed contacts 145, to the line conductor 113. The pusher returns all the way and operatesthe rear limit switch 102, breaking the current in conductor 144 and normalizing the reverse relay 142. This action opens contacts 145 on the revgrse relay and cuts off the current in the reverse soleno1 The pusheribar isnow all theway out in its starting position; the rack bar 90 isin its zero position with contacts 133'resting against contacts 134 and all the relays have been normalized. This wasthe condition when the operation was started and the apparatus is now set to go through another. full cycle to load the new platen. The abovedescribed controlled. operation is performedover and overagain as; each platen isfilled... When thelast platen is filled theUp solenoid controls the vertical piston to move -the.platen. arrayupward until-a rod -105- secured to the upper portion of the platenframe-g162:movcs upper limit switch 104 causing a circuit to be completed throughwaqholeeinithe upper wall- ,12 andoperetes: the

whichtactuatesthe. catcheB relay winding/119; therebyb'reaking contacts 154* and cutting off the current through the-Up:.solenoid winding 93. The, platen. arraynow. driftszdownwardly the entire distance and all the. platens 3.1'8 10W8I'6d1i111l0 a;freezing well where they mayzall'zbe frozen. to .the required temperature. The catches. 157' and- 158 are mechanically held away from the platen edges by-means of aliat strip 174 and a pin 175 secured tothe catch- As the platen array moves downwardfthe pin 175 rides onthe outside of strip 174 until the entire array of platens is in the lower position. At this point the pin 175 moves over the top .of strip 174and the catchesare again permitted to make contact with' the edges of the platen.

The platen array remains in its lowered position until all the boxes are frozen. At this time an operator may start another filling and freezing cycle by manually pressing the start button and: starting another-complete. cycle as described above. However, if the freezing time is accurately known atiming device may be employed to start a new cycle byautomatic means. The components ofthis circuit include a timing motor 176 which runs all the time; an electric clutch 177 secured to the-shaft of the timer motor, a timer device 178 which may bea set of reduction gears set to operate a lever 180, and a pair of contacts 181 in series with the-start button which are opened when lever 180 is operated. The operation of this circuit is obvious; as soon as the platen array settles to its lowest position a lower limit switch'150 is operated and contact is made which energizes the electric clutch 177. The timer motor 176 then turns the timer mecha nis'm;178 until, after a predetermined length of tithe,- lever 180 is' operated and the timer contacts 181 are opened.

When-the platenarray is in its lowestpositionswitch 96 is operated, thereby sendingcurrent from conductor 113through switch-96, then over conductor 182 to the Downsolenoid 95, and line conductor 124. The Down solenoid opens the valve which causes a slight pressure to be'exerted'on the platens to hold them in closecontact with the food packages and permit a more efiicient freezing operation.

While the above described device has been designed primarily for automatic action, means have been provided for hand operation. The main switch 132 maybe turned to make contact with the manual contact Man. and certain push buttons can be then operated to give step-by-step operation.

With the pusher in its fully retracted position the knob 97'makes'contact with switches 102 and .103, thereby forming a circuit which keeps motor 106 running. Now, if the forward For. button 185 is depressed, a circuit (is completed which can be traced from oneof the manual conductors 186, through the For. switch contacts, to'the For. winding 77 of the forward solenoid, and the other side. of the supply line 124. This operates the solenoid core 75 and moves the valve 74 to operate piston .67 (Fig. 7) and move the pusher in the first part of its cycle to pushthe boxes into the space between twoplatens.

After the pusher has moved to the position denoted by FL, forward,limit, or to. FFL, full forward Ii'mit,,the button is,released and .the,reverse button Rev. 18.7.is depressed. This button completes a circuit, whichmay be. traced. from conductor 186,through the contacts under button. 187, to the solenoid winding 76 of the Rev. reverse'solenoid, and core 79 is operated. to move the valve piston 74 and cause the power piston.67 to. bring thepusherback to its normal or startingpositiont.

By succeesive operations of the For. and Rev. buttons an entire platen can, be loaded. Next the Up manual button 188 is depressed and circuit is broken .through contact arm- 156 .but closedthrough arm-19.0.. This action completes a circuit-which may be traced-from ,a second manual line-conductor 191,. through the. rear limit switch arm 103, to the conductor 192, switch arm 190, solenoid winding 93, and the line conductor 124. This,circuit operates only when the pusher is all the way out and the rear limit switch 102, 103 in its operated condition. The Up solenoid core operates a valve similar to the valve shown in Fig. 7 and the platen array is slowly moved upward. It is necessary for the operator to listen for the sounds of the catches 157 and 158 as they snap into position under the platen. As soon as these sounds are heard the Up button 188 is released and the cycles of the pusher can be resumed by alternate depressing of the For. and Rev. buttons 185 and 187.

The manual buttons may be used to test the apparatus prior to starting the automatic operation.

While there have been described herein what are at present considered preferred embodiments of the invention, it will be obvious to those skilled in the art that many modifications and changes may be made therein without departing from the essence of the invention. It is therefore to be understood that the exemplary embodiments are illustrative and not restrictive of the invention, the scope of which is defined in the appended claims, and that all modifications that come within the meaning and range of equivalency of the claims are intended to be included therein.

What we claim is:

1. A pusher assembly for automatically feeding columns of packages from a conveyor toa plate freezer having generally aligned front and rear wall openings to receive and discharge the packages comprising a lever pivoted at a point adjacent to said plate freezer, a pusher bar mounted on the lower end of the lever, a power means coupled to the upper end of the lever for moving the lower end of the lever toward and away from the front wall opening, said power means controlled by sensing devices responsive to the position of the lever, and control means for positioning the pusher bar to engage the column of packages when the pusher bar moves toward the front wall opening and to rise above said column when moving away from said opening, said control means comprising a-link pivoted at one end on the pusher bar and provided with a pin adjacent the opposite end, and a movable cam block engaging said pin and controlling it to move in a predetermined path as the lever is moved toward and away from the front wall opening.

2. A pusher assembly for automatically feeding columns of packages from a conveyor to a plate freezer having generally aligned front and rear wall openings to receive and discharge the packages comprising a lever pivoted at a point adjacent to said plate freezer, a pusher bar mounted on the lower end of the lever and arranged parallel to said columns of packages on the conveyor; a power means connected to a rod and arranged to move the rod in two directions, coupling means between the rod and said lever, said power means controlled by sensing devices responsive to the position of said lever, and control means for positioning the pusher bar to engage the column of packages when the pusher bar moves toward the front wall opening and to rise above said column when moving away from said opening, said control means comprising a link pivoted at one end on the pusher bar and provided with a pin adjacent the opposite end, and a movable cam block engaging said pin and controlling it to move in a predetermined path as the lever is moved toward and away from the front wall opening.

3. A pusher assembly for automatically feeding columns of packages from a conveyor to a plate freezer having generally aligned front and rear wall openings to receive and discharge the packages comprising a lever pivoted at a point adjacent to said plate freezer, a pusher bar mounted on the lower end of the lever and arranged parallel to said columns of packages on the conveyor, a power means connected to a rod and arranged to move the rod in two directions, coupling means between the rod and said lever, said power means controlled by sensing devices responsive to the position of said lever, and con trol means for positioning the pusher bar to engage'the' column of packages when the pusherbar moves toward the front wall opening and to rise above said column when moving away from said opening, said control means comprising a link pivoted at one end on the pusher bar' and provided with a pin adjacent the opposite end, and a movable cam block engaging said pin for motion-along one path when the lever is moved toward the front 'wall opening and engaging the pin after a full forward move ment for motion along another path when the lever is moved in the opposite direction.

4. A pusher assembly for automatically feeding col-' umns of packages from a conveyor to a plate freezer having generally aligned front and rear wall openings to receive and discharge therpackages comprising a lever pivoted at a point adjacent to said plate freezer, a pusher bar mounted on the lower end of the lever and arranged parallel to said columns of packages on the conveyor, a sensing means coupled to said packages which is operated when the conveyor is filled with packages, a power means connected to a rod and arranged to move the rod in two directions, coupling means between the rod and said lever, said power means controlled to start the pusher bar to engage a column of packages when said sensingmeans is operated, and control means for moving the pusher bar to move said packages into the front wall opening, said control means comprising a link pivoted at one end on the pusher bar and provided with a pin adjacent the'opposite end, and a movable cam block pivoted'near one side thereof for guiding said pin along one path when the lever is moved toward the front wall opening and guiding the pin for motion along another path when the lever is moved in the opposite direction.

5. A pusher assembly for automatically feeding columns of packages from a conveyor to a plate'freezer having generally aligned front and rear wall openings to,

receive and discharge the packages comprising a lever pivoted at a point adjacent to said plate freezer, a pusher bar mounted on the lower end of the conveyor, a cylinder with a piston coupled to said lever, fluid means for moving the piston in both directions in the cylinder to move the pusher bar toward and away from the front wall opening, said fluid means controlled by sensing devices responsive to the position of the lever, and control means for positioning the pusher bar to engage the column of packages when the pusher bar moves toward the front wall opening and to rise above said column when moving away from said opening, said control means comprising a link pivoted at one end on the pusher bar and provided with a cam follower adjacent the opposite end, and a movable cam block engaging said follower for motion along one path when the lever is moved toward the front wall opening and engaging the follower after a forward movement for motion along another path when the lever is moved in the opposite direction.

6. A pusher assembly for automatically feeding columns of packages from a preset position to an extended area through a wall opening, a lever pivoted adjacent to said wall, a pusher bar mounted'on one end of said lever, a power means coupled to the other end of said lever for moving the pusher bar toward and away from said wall opening, said power means controlled by sensing devices' responsive to the position of the pusher bar, and control means for vertically positioning the pusher bar to engage the column of packages when the pusher bar is moved toward the wall opening and to rise above said column when moving away from said opening, said control means comprising a link pivoted at one end on the pusher bar and provided with a cam follower adjacent the opposite end, and a cam containing a movable component for engaging said follower and guiding it in a predetermined a 11 pgth u thenlever isrnovedtoward and away from the \vdltopeningr RA pusher assembly for automatically feeding, col: W Ofpackages from a conveyor to a plate freezerhavgenerally aligned: front and rear wall openings to rmive'anddischarge,the packages comprising a lever pivotqdat aipoint adjacent to said plate freezer, a pusher bar muntddlml; the lower;end of the lever, a power means coupledeto the upper endof the lever for moving the Iowan end ,ofthe lever toward and away from the front wall mpeningsaidpower means controlled by sensing devices responsive to the position of the lever, control meanssfortpositioning the pusher bar to engage the columngflpackages when the pusher, bar moves toward the from wall opening andtoprise above said column when myingtawaylfrom said opening, said control means coma link pivotedat oneend on the pusher bar-and with alp in adjacent theopposite end, and a movablescamrblock engaging said pin andcontrollingit to mye dn a; predetermined path as the lever is moved towardmndmway fromrtheufront wall opening, andmeans under; control of said, sensing devices for moving the ppshqnbar" an extra increment of travel on, the first movemgntina-cyclicoperation tomove prior positioned packaggs withinthe; wall opening; before. a new column of ppckagesis moved therein.

8. A pusher assembly for automatically feeding colmn ,,,of-,,packages from' a conveyor to a, plate freezer hawing generally aligned front and rear wall openings tutrwcive 1. and. discharge the packages comprising: a lever pivoted at arpoint adjacent to said plate freezer, a pusher banmounted on the lower end of the lever, a cylinder Within pistoncoupledtosaid lever, fluidmeans for moving the piston in both directions in the cylinder to move the pushertbartoward andwaway from the front wall opening said-,fluid means controlled by sensing devices responsive tor the position of thelever, control means for .posi tioningthepusher bar, to engage, the column of packagesrwhen the pusher bar moves toward the front .wallzopening andto, rise above said column when moving .awayirom said ropening, said control means comprising alihkpivotedat one end on the-pusher bar, andprovided with, aecamnfolloweradjacent/the opposite end, and a movable. cam. blocktengaging said follower: for, motion .along,ion e-path. when the lever is moved, toward vthe front iwall, opening andengagingwthe, follower after a forwardmovement for. motion along another path. when the lever is moved in the opposite direction, and means undercontrolf of said sensing devices for moving the pusher vbar an extra increment of travel on the first move- 121 V merit. in, a cyclic operation-to move prior positioned packageawithin the wall Opening before a new column of packagesis' moved therein.

9. Apusher assembly for automatically feeding columns of packages from a preset position to an extended area through a wall opening, a lever positioned adjacent to said wall, a pusher bar mounted on one end of said lever, a power means coupled to the other end of said lever for moving the pusher bar toward and away from said wall opening, said power means controlled by a plurality of electrical switches which are actuated by means coupled tosaid lever and responsive to the position of the pusher bar, and control means for vertically positioning thepusher bar to engage the column of packages when the pusher bar is moved toward the wall opening and to rise above said column when movingaway from said opening, said control means comprising a linkpivoted at one end on the pusher bar and provided with a cam follower adjacent the opposite end, and a cam containing a movable component for engagingsaid follower and guiding it in apredetermined path as the lever is moved toward and-away from the wall opening.

10. A pusher'assembly' for automatically feeding columns of packages from a conveyor to an extended area through a wall opening comprising a lever pivoted at a point'adjacent to said wall, a pusher bar mounted on the lowerend ofthe lever and arranged parallel to said columns of packages on the conveyor, a sensing means coupled to saidpackages which is operated when the conveyorzis filled with packages, said sensing means including a motor resiliently mounted on said wall, an overrunning clutch and wheel run by the motor, and an electrical switch-mounted on the wall and actuated by the motor, a power means connected to a rod and arranged to move the rodin two directions, coupling means between the rod. and said lever, said power means controlled to start the pusher bar to engage a column of packages when=said switch is actuated, and control means for moving the pusher barto move said packages-into the front wall opening, said controlmeans comprising a link pivoted at one end on the pusher bar and provided with a pin adjacentitheopposite end, and a movable cam block pivoted near one side'thereof for guiding the pin along one path when the lever'is moved toward the wall opening and forguidingthe pin: for motion along another path when thelevcris movedin the opposite direction.

References Cited in the file of this patent UNITED STATES PATENTS 2,390;'-72,5 McNamara Dec. 11, 1945 

